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Author
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Topic: can i use dental stone instead of ultracal or whitecal
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blue
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posted 01-25-2001 05:57 AM
i`m gona make life cast, but i don`t know if i can use dental stone(plaster) instead of ultla or whitecal.
For bake it in oven , does it work well?
i mean, does dental stone endure of heat in oven. i want to make sure how differant dental stone and normal plaster which is break easily.
can i use dental stone?And, i`m just wonder how much time wait after alcoat use(coat)over positive cast for sculputure with oil based clay.
and how much time wait after it soak in water.
thanks friend!!!^.^
[This message has been edited by blue (edited 01-25-2001).] |
Jeff F
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posted 01-25-2001 01:55 PM
Some dental stones are acceptable substitutes for Ultracal 30. Different companies make dental stone and the characteristics vary from company to company, while Ultracal 30 & 60 are only made by US Gypsum. Dental stone is denser and usually takes longer to set, and is slightly less accurate.Ultracal 60 is stronger than 30, but takes a longer time time to set - Ultracal 30 is considered standard. Ultracal 30 isn't quite as durable as it used to be, so some artists prefer epoxy resin molds for high accuracy, durable molds. Not sure what you are referring to when you mention "whitecal"? Perhaps white Hydrocal? This is good for various molding purposes but not ideal for molds that are to be baked. ------------------
Jeff F - Moderator
Magic and FX
Amazing the Masses |
morpherguy
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posted 01-25-2001 04:57 PM
Yes, you can use dental stone. Johnny Chambers used it all the time. Mr. Chambers is the man responsible for the Planet of the Apes make up. He won the first academy award ever given out for make up. He won it before there was even a make up catagory..[This message has been edited by morpherguy (edited 01-25-2001).] |
Jeff F
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posted 01-25-2001 08:30 PM
Good point - methods evolve as new materials become available and offer additional advantages.Jack Pierce built Frankensten's monster head on Boris Karloff with nothing more than cloth, cotton, spirit gum, and collodion. Astounding that he could get consistent results this way! Dick Smith used to use R & D foam latex and invented the overlapping prosthetics technique to help counter act the terribly unreliable amount of shrinkage in that product - the best that was generally available at the time. Moulage was used prior to alginate for the molds lifecasts were made from. White plaster of paris before that (ugh!) You work with the materials available at the time and coax the best that you can out of them, and the real masters got a lot out those materials. Dental stone does indeed work, but many make up artists today prefer Ultracal 30 and epoxy resins for rigid, heat resitant molds. Actually, more and more make up artists are swearing off cements and stones altogether, but Ultracal is still good enough for little 'ol me.  ------------------
Jeff F - Moderator
Magic and FX
Amazing the Masses |
blue
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posted 01-26-2001 02:55 AM
And, i`m just wonder how much time wait after alcoat use(coat)over positive cast for sculputure with oil based clay.
and how much time wait after it soak in water.
thanks friend!!!^.^
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morpherguy
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posted 01-26-2001 08:41 AM
You need to put the Alcote on as soon as possible after you make the positive head cast. If you wait too long (a day) the stone or plaster will be too dry and will tend to suck the water out of the Alcote before it has a chance to soak in. If the head cast is too dry just soak it in water for an hour then apply the Alcote. I always let the sculpture sit in a tub of water for at least 24 hours before trying to remove them from the alcoted head cast. |
crazy lou
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posted 01-27-2001 03:16 AM
yeah thats what i do. I soak the sculpture for about that long, but i do it in cold water so the clay hardens and doesnt break or loose any detail when i'm touching it. later
Tom ------------------
What everyone seems to forget is that once we look past race, religion, gender, and all that, everyone on this planet is first and foremost... ...a PERSON LINKS(added to 01/16/01) |
